1. Field of the Invention
The invention relates to a method and apparatus for determining yarn number or thickness deviations in yarn connecting processes of automatic open-end spinning machines.
2. Description of the Related Art
As is known, yarn connections are always necessary in automatic open-end spinning machines when the thread breaks, has to be cut due to faulty formation, or if the sliver supply runs out and new sliver must be inserted.
Although as a rule the yarn splicing region itself is monitored, in order to make certain that no yarn connections of unacceptable dimensions, strength, or poor appearance are in the yarn, it must be assured that there is no possibility for other less conspicuous yarn number or thickness deviations to remain undetected.
It is also possible for a slight yet permanent change in the yarn number or the yarn thickness to occur and remain undetected due to its small magnitude, when introducing new sliver. The above-mentioned yarn number or thickness deviations dealt with in this case are not visible with the naked eye. They will only become visible, if at all, in the finished fabric subsequently made from this yarn.